wsus can't auto update

internal wsus server can't update.
when use Client Diagnostics Tool check all pass.
windows install in d drive
why??
thanks!!!

2009-04-06 10:02:15:843 1176 e04 Agent *************
2009-04-06 10:02:15:843 1176 e04 Agent WARNING: WU client failed
Searching for update with error 0x8024400e
2009-04-06 10:02:15:859 1176 ca0 AU >>## RESUMED ## AU: Search for
updates [CallId = {E9391ABA-E65F-449E-B783-8FD715AA479E}]
2009-04-06 10:02:15:859 1176 ca0 AU # WARNING: Search callback
failed, result = 0x8024400E
2009-04-06 10:02:15:859 1176 ca0 AU # WARNING: Failed to find
updates with error code 8024400E
2009-04-06 10:02:15:859 1176 ca0 AU #########
2009-04-06 10:02:15:859 1176 ca0 AU ## END ## AU: Search for
updates [CallId = {E9391ABA-E65F-449E-B783-8FD715AA479E}]
2009-04-06 10:02:15:859 1176 ca0 AU #############
2009-04-06 10:02:15:859 1176 ca0 AU AU setting next detection timeout
to 2009-04-06 07:02:15
2009-04-06 10:02:15:859 1176 ca0 AU Setting AU scheduled install time
to 2009-04-10 07:00:00
2009-04-06 10:02:20:843 1176 e04 Report REPORT EVENT:
{AEFDDFBC-0A65-4F84-AF8C-EF3E16B6BCB1} 2009-04-06 10:02:15:843+0800 1
148 101 {00000000-0000-0000-0000-000000000000} 0 8024400e
AutomaticUpdates Failure Software Synchronization Windows Update
Client failed to detect with error 0x8024400e.
2009-04-06 10:05:44:546 1176 81c AU AU found 0 updates for install at
shutdown
2009-04-06 10:05:44:593 2636 6c4 Misc =========== Logging initialized
(build: 7.0.6000.374, tz: +0800) ===========
2009-04-06 10:05:44:593 2636 6c4 Misc = Process: D:\WINDOWS
\Explorer.EXE
2009-04-06 10:05:44:593 2636 6c4 Misc = Module: D:\WINDOWS
\system32\wuaueng.dll
2009-04-06 10:05:44:593 2636 6c4 Shutdwn Install at shutdown: no
updates to install
2009-04-06 10:06:10:687 1176 f9c AU ########### AU: Uninitializing
Automatic Updates ###########
2009-04-06 10:06:11:328 1176 f9c Service *********
2009-04-06 10:06:11:328 1176 f9c Service ** END ** Service: Service
exit [Exit code = 0x240001]
2009-04-06 10:06:11:328 1176 f9c Service *************
2009-04-06 11:11:38:515 1116 378 Misc =========== Logging initialized
(build: 7.0.6000.374, tz: +0800) ===========
2009-04-06 11:11:38:546 1116 378 Misc = Process: D:\WINDOWS
\System32\svchost.exe
2009-04-06 11:11:38:546 1116 378 Misc = Module: D:\WINDOWS
\system32\wuaueng.dll
2009-04-06 11:11:38:515 1116 378 Service *************
2009-04-06 11:11:38:546 1116 378 Service ** START ** Service: Service
startup
2009-04-06 11:11:38:546 1116 378 Service *********
2009-04-06 11:11:38:546 1116 378 Agent * WU client version
7.0.6000.374
2009-04-06 11:11:38:546 1116 378 Agent * Base directory: D:\WINDOWS
\SoftwareDistribution
2009-04-06 11:11:38:546 1116 378 Agent * Access type: No proxy
2009-04-06 11:11:38:546 1116 378 Agent * Network state: Connected